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Bloxiverz Side Effects

Generic Name: neostigmine

Note: This document contains side effect information about neostigmine. Some of the dosage forms listed on this page may not apply to the brand name Bloxiverz.

For the Consumer

Applies to neostigmine: injection solution

Along with its needed effects, neostigmine (the active ingredient contained in Bloxiverz) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking neostigmine:

More Common

  • Blurred or loss of vision
  • chest pain, discomfort, or tightness
  • confusion
  • difficult or labored breathing
  • dizziness, faintness, or lightheadedness when getting up from a lying or sitting position suddenly
  • fast, slow, pounding, or irregular heartbeat or pulse
  • lightheadedness, dizziness, or fainting
  • sweating
  • twitches of the muscle visible under the skin
  • unusual tiredness or weakness

Incidence Not Known

  • Changes in patterns and rhythms of speech
  • cough
  • difficulty in moving
  • difficulty swallowing
  • disturbed color perception
  • double vision
  • halos around lights
  • hives
  • irregular, fast or slow, or shallow breathing
  • itching
  • loss of consciousness
  • muscle cramps and spasms
  • muscle pain or stiffness
  • night blindness
  • no blood pressure or pulse
  • noisy breathing
  • overbright appearance of lights
  • pain in the joints
  • pale or blue lips, fingernails, or skin
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • seizures
  • skin rash
  • slurred speech
  • stopping of the heart
  • trouble in speaking
  • tunnel vision
  • unconsciousness

Get emergency help immediately if any of the following symptoms of overdose occur while taking neostigmine:

Symptoms of Overdose

  • Constipation
  • decreased sexual ability
  • difficult urination
  • dry mouth
  • enlarged pupils
  • muscle weakness

Some side effects of neostigmine may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More Common

  • Bleeding, blistering, burning, coldness, discoloration of skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at site
  • drowsiness
  • headache
  • increased watering of the mouth
  • nausea
  • sleeplessness
  • sore throat
  • trouble sleeping
  • unable to sleep
  • vomiting

Incidence Not Known

  • Bloated
  • constricted, pinpoint, or small pupils (black part of eye)
  • diarrhea
  • dry mouth
  • excess air or gas in the stomach or intestines
  • feeling of warmth
  • full feeling
  • increase in mucous from the lungs
  • increased need to urinate
  • increased sweating
  • passing gas
  • passing urine more often
  • redness of the face, neck, arms and occasionally, upper chest
  • redness of the skin
  • skin rash
  • stomach cramps

For Healthcare Professionals

Applies to neostigmine: compounding powder, injectable solution, intravenous solution, oral tablet


The most common side effects included salivation, fasciculation, bowel cramps and diarrhea.[Ref]


Common (1% to 10%): Bradycardia, hypotension, tachycardia

Frequency not reported: Nonspecific EKG changes, cardiac arrest, syncope

Postmarketing reports: Cardiac arrhythmias (A-V block, nodal rhythm)[Ref]


Common (1% to 10%): Pruritus

Frequency not reported: Rash, urticaria[Ref]


Common (1% to 10%): Dry mouth, nausea (including post-procedural), vomiting

Frequency not reported: Flatulence, increased peristalsis

Postmarketing reports: Bowel cramps, diarrhea[Ref]


Frequency not reported: Urinary frequency[Ref]


Frequency not reported: Allergic reactions and anaphylaxis[Ref]


Frequency not reported: Muscle cramps and spasms, arthralgia

Postmarketing reports: Muscle weakness[Ref]

Nervous system

Common (1% to 10%): Dizziness, headache, postoperative shivering, prolonged neuromuscular blockade, insomnia

Postmarketing reports: Convulsions, drowsiness, dysarthria, fasciculation, loss of consciousness[Ref]


Frequency not reported: Miosis, visual changes[Ref]


Common (1% to 10%): Incision site complication, procedural complication and pain

Frequency not reported: Diaphoresis, flushing, weakness[Ref]


Postmarketing reports: Urinary frequency[Ref]


Common (1% to 10%): Pharyngolaryngeal pain, dyspnea, oxygen desaturation (less than 90%)

Frequency not reported: Increased oral, pharyngeal and bronchial secretions, dyspnea, respiratory depression, respiratory arrest, bronchospasm[Ref]


1. "Product Information. Bloxiverz (neostigmine)." Eclat Pharmaceuticals, Menomonee Falls,, WI.

2. "Product Information. Prostigman (neostigmine)." ICN Pharmaceuticals Inc, Cost Mesa, CA.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.